Die for forming clay.



me Fon Formula CLAY. ,(Application led June 18, 1900.)

Patented Dec. 4, |900. W. WALKER H. W. CROFT.

JON

(No Model.)

desired shape.

` `NiTED STATES PATEN WILLIAM WALKER, OF ALLEGI-IENY, AND HARRY W.OROFT, OF PITTSBURG,

' PENNSYLVANIA.

DIE FOR FoslvllNeoLAY.

SPECIFICATION forming part of Letters Patent No. 663,140, dated December4, 1900. Application iiled Juile 18, 1900. Serial No. 20,687. lNomodel.)

To a/ZZ whom it may concern:

Be it known that we, WILLIAM WALKER, a resident of Allegheny, and HARRYW. OROFT, a resident of Pittsburg, in the county of Al- 5 legheny andState of Pennsylvania, have invented a new and useful Improvement inDies for Forming Clay; and we do hereby declare the following to beafull, clear, and ex'- act description thereof.

Our invention relates to apparatus for the manufacture of sewer-pipe,bricks or blocks, or other objects made by forcing clay or fireclay intoor through molds, dies, or nozzles for the purpose of forming the sameinto the I-Ieretofore these blocks or bricks have been made by formingthem with flat parallel faces in dies conforming exactly to the finishedblock to be produced. It is found, however, that after the block leaveszo the die the sides assume a slightly-convex shape, so that the blockswill not iit close to each other, asis particularly desirable inconnection with the building of glass-furnaces, blast-furnaces, hearths,and like work, where z 5 it is important for the blocks to fit closelyto prevent flux materials from working into the joints. This defect isparticularly noticeable in heavy large blocks containing a large mass ofclay. The reason for this is not abso` 3o solutely understood, though itis believed to arise from the air occluded in the mass of clay andbrought under compression in passing through the die and which graduallythereafter expands and changes the form of the 5 5 block. In order tomake such bricks or blocks iit closely, it has been found necessary togrind their surfaces to a straight line after the material was dried.This, however, de-

stroys the natural glaze given the material 4o in the die and not onlyweakens the blocks, but also diminishes their power to resist the actionof iux materials.

One object of our invention is to overcome this defect and provideapparatus whereby such blocks or bricks may be so shaped that when driedand burned the faces thereof shall be substantially hat and parallel.This object we secure by providing the die by which thereof, withgradually-tapering sides 3 and the blocks are molded with convex innersurfaces.

A further object of our invention is to provide the die with removablelining-plates, so that worn-out plates can be replaced by new ones orthe shape or size of the die changed by inserting lining-plates of thedesired size l or shape.

Our invention has been found to be especially advantageous in themanufacture of large heavy fire-clay blocks, and the manufacture of suchblocks has therefore been illustrated in describing the invention. Theinvention, however, is not limited to the manufacture of such blocks,but may advantageously be used in the manufacture of various objectsmade by compressing clay or the like.

To enable others skilled in the art to make and use our invention, wewill describe the samev more fully, referring to the accompanyingdrawings, in which- 7o Figure l is a longitudinal section of the pressand die used for formingthe blocks. Fig.

2 is a cross-section of the die on the line 2 2,

Fig. l. Fig. 3 is a perspective view of one'of the removablelining-plates. Fig. Lis a per- 75 spective view of a block, showing itsshape as it passes through the die, the concavity of the sides oftheblock being exaggerated somewhat. Fig. 5 is a perspective view of thesame block after the sides thereof have expanded to form substantiallyflat faces; and Fig. 6 is a view in side elevation of the stool used toshape the end of the block, with a block therein to illustrate themanner in which it is used.

Like reference-numerals indicate like parts in each view.

In the drawings,l indicates an ordinary reclay press having the bowl 2at the base 9o the die or nozzle 4 secured thereto. The clay is forcedfrom the press into the bowl and through the die by any suitable means.The inner faces of the die are made slightly convex, as shown at 5, thedegree of convexity depending generally upon the width and thickness ofthe blocks and the bulk of clay present, it being possible to ascertainpractically the proper amount of convexity to be given to the die toproduce the flat sides on a block of given bulk. For example, with astiff body of claya convexity of three thirtyseconds of an inch in awidth of about fourteen inches is found to be substantially correct inorder to produce the straight sides or faces of the blocks, though ofcourse this is to be varied as found-necessary.

The block is received upon the receding table 6 and when of sufficientlength is cut off by the wire knife 7, secured to the rockshaft 8,journaled in the side of the die and press. These parts are old and wellknow-n in machines of this class, and their operation will be readilyunderstood without further description.

The die may be provided with removable lining-plates 9, secured thereinby means of the bolts 10. As shown in the drawings, two lining-platesare provided; but it is obvious that any suitable number may beemployed. In case it is desired to form blocks with substantially fiator parallel 'sides the liningplates will be provided with convex innersurfaces in the same manner as the die. As illustrated, these plates arecut away at the back, as shown at 11, in order to lighten them and toinsure a better seating on the inner surface of the die. They arebeveled or flared at their upper ends, as shown at l2, in order to forma continuation of the inclined inner surface of the bowl 2. They arelikewise provided with projecting lips 13 on their edges to formslightly-rounded corners on the blocks. When the inner faces of the dieare convex, the edges of the plates are formed on lines acute to theback face, as shown at 14, to t closely the convex inner surfaces of thedie. In the specific form illustrated the bowl 2 has a projectingshoulder l5, under which the lining-plates are secured, so that theinclined walls 3 of the bowl and the inclined portion 12 of the platesform an unbroken surface.

The stool illustrated in Fig. 6 consists of a horizontal rectangularframe 16, having two of its sidevmembers provided with concave topsurfaces, as shown at 17, and provided with four depending legs 18, andit is adapted to ft over the block after it is pressed to shape and forma guide for cutting a concave top face 21, a wire knife 2O beingemployed for this purpose.

In the operation of the apparatus the clay is brought to the properconsistency and is fed to the press and forced into the bowl 2 andthrough the die or nozzle 4, the blocks being received upon the recedingtable 6, and when of proper length are cut off by the wire knife 7. Inpassing through the die or nozzlevthe side faces of the blocks areformed slightly concave, as illustrated at 19, Fig. 4. When it is alsodesired to provide the burned vagain fastening the bolt 10.

blocks with fiat end faces, the stool is slipped over the block, asshown in Fig.l 6, and by means of the wire knife 20, guided on theconcave surfaces 17, the end of the block is cut off and the desiredconcave end face formed, as shown at 21, Fig. 4. This face is thensmoothed with a paddle or other suitable tool to impart the desiredglaze thereto. After the blocks are so formed they are placed on asuitable drying-floor'and permitted to dry before baking. It is foundthat in drying they expand through the occluded air under compression inthe blocks or from some other cause,rso that the concave faces 19 and 21are brought out practically parallel or fiat, as shown in Fig. 5. Y

By replacing the removable lining-plates 9 by others of different shapesor sizes a single machine may be used to form blocks of different sizesor shapes. Furthermore, when a lining-plate becomes worn it can bereplaced by a new one at a less expense than if the en- .tire die ornozzle had to be replaced. The

construction illustrated is of such a nature that the plates can bereadily removed and replaced by others by merely loosening and Thisfeature is of considerable value in presses that are used for makingmerely rough blocks or bricks which need not be provided with absolutelydat surfaces. In such cases the lining-plates would be provided withflat faces and merely serve as wearing-surfaces for the die. By the useof a die provided with convex inner surfaces it is possible to formblocks having side faces which when dried or burned are substantially ator parallel, thereby obviating the necessity of grinding the faces,ashas heretofore been done.

What we claim as our invention, and desire to secure by Letters Patent,is-

1. In apparatus for forming fire-clay or like blocks, the combination ofa die provided with convex inner faces, removable lining-plates for saiddie, provided with convex inner faces and acute-angled edgescorresponding to and adapted to closely fit the curved inner faces ofthe die.

2. In apparatus for forming fire-clay or like blocks, the combination ofa die and removable lining-plates for said die, provided with projectinglips 13 on the edges thereof.

3. In a press for forming fire-clay or like blocks, the combination witha press, of the bowl provided with inclined sides, the die or nozzlesecured thereto, and the removable lining-plates fitted in the die andprovided at their upper ends with beveled or inclined surfaces to form acontinuation of the inclined sides of the bowl.

4. In a press 'for forming fire-clay or like blocks, the combinationwith a press, of the bowl provided with inclined sides and projectingshoulders 15, the die or nozzle secured thereto, and the re movablelining-plates fitted IOO in the die and abutting against said shoulders,and provided at their upper ends with beveled or inclined surfaces toform a oon- In testimony whereof We, the said WILLIAM 1o WALKER andHARRY W. CROFT, have hereunto set our hands.

WILLIAM WALKER. HARRY W. CROFT.

Witnesses:

S. C. WALKER, ROBERT C. To'rTEN.

